Rotary hook sewing machine



arch 1957 R. GIANINAZZI ROTARY HOOK SEWING MACHINE Filed Jan. 20, 1964 IN VENTOR "ROLANDO GIANJ NAZZ! V TTORNEY United States Patent Ofiticc 3,308,777 RGTARY HOOK SEWING MACHINE Rolando Gianinazzi, Geneva, Switzerland, assignor to Mefina S.A., Fribourg, Switzerland, a corporation of Switzerland Filed Jan. 20, 1964, Ser. No. 338,887 Claims priority, application Switzerland, dune 26, 1963, 8,070/63 1 Claim. (Cl. 112186) The present invention concerns rotary hook sewing machines.

According to the present invention an extracting device for the spool is fixed to the head of the machine and is adapted to permit the retraction of the spool from its housing.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which:

FIGURE 1 is a front view in elevation, with partial section, of a sewing machine in accordance with the invention;

FIGURE 2 is a detailed view, on an enlarged scale; and

FIGURE 3 is a partial view, in plan, showing the position of the spool of this sewing machine.

This sewing machine comprises a frame formed of an upper part 1, terminating in an overhanging head 2, and a work supporting lower part 3 or free arm. This upper part 1 and lower part 3 are connected by a column, not shown. The needle bar 4 slides vertically in this head 1. In the sewing machine shown, this needle bar 4 slides in bearings 5 and 6 forming part of a movable cradle 7. This movable cradle 7 is adapted to oscillate around a vertical axle 8 fixed in the upper frame 1 of the machine as illustrated and described in US. Patent No. 2,682,845. A circlip 9 engaged in a throat 10 of the vertical axle 8 ensures the axial position of the cradle 7 on this axle 8. The head 2 of the upper frame 1 likewise carries the material presser bar 11 adapted to receive the different types of presser foot, not shown.

The vertical axis rotary hook 12, arranged in the lower part 3 of the frame, or free arm, is secured to a pinion 13 actuated from a horizontal shaft 14 by means of a tangent screw 15. The spool 16 is arranged in the central part of this rotating hook 12 and retained in place by the upper cap 17. This spool 16 presents a central bore, or usual barrel 18. The free arm 3 is closed in its upper part by a cover 19 in which is made an opening for a needle hole plate, not shown.

The vertical axle 8 of this sewing machine is tubular and is adapted to serve, in part, to house an extracting device for the spool 16. This device, which is fixed to the head 2 of the sewing machine, comprises a finger 20 preferably in soft plastics material. This finger 20 presaid lower part and 3,308,777 Patented Mar. 14, 1967 sents an enlarged part 21 adapted to facilitate the holding thereof. It is, moreover, provided with an extension 22 adapted to be engaged in the bore 23 of the tubular axle 8. This bore 23 likewise serves for housing a coil spring 24, the upper end 25 of which is fixed around a screw 26 retained by its head 27 at the upper end of the tubular axle 8. The lower end 28 of the spring 24 is forced around the extension 22. This spring 24 constitutes, in effect, a return spring adapted to retract the finger 21) into the retracted position of non-use.

To increase the suppleness of the finger 20, this presents two intersecting transverse slots 29.

The use of the extracting device for the spool is effected in the manner described below.

After having removed the usual protecting cover of the spool, not shown in the drawing, the user of the machine takes the enlarged part 21 between his fingers and pulls the finger 2d downwardly, against the action of the spring 24, to engage it in the bore 18 of the spool 16. This engagement is effected with a light friction, the finger 20 being of slightly larger section than the bore 18. In releasing the enlarged part 21, the spring 24 draws the finger 20 and the spool 16 together upwardly. The spool 16 can then be easily disengaged from the finger 20, either for replacing by a spool carrying another type of thread or to recharge with a certain quantity of thread.

I claim:

In a rotary hook sewing machine, including an overhanging machine head, a vertical axle carried by the head, a cradle adapted to oscillate around said axle, a needle bar vertically slidable in the cradle, a work supporting lower part, a vertical axis rotary hook disposed Within presenting a housing adapted to contain a spool to provide a lower thread supply, finger means of soft plastic material displaceably mounted on the head for engaging in a central bore of the spool to retract the spool from the hook housing, and coil spring means urging said finger means into an inoperative position relative to the head, said vertical axle being tubular and housing said spring means, said finger means presenting an extension partially engaged in said tubular axle when in said inoperative position.

References Cited by the Examiner UNITED STATES PATENTS 114,294 5/1871 House et a1 112-184 906,987 12/1908 Angus 1l2186 2,438,459 3/1948 Sebell 112.186 2,690,725 10/1954 Schumann et a1 112186 3,125,973 3/1964 Bernerus et a1. 112-186 JORDAN FRANKLIN, Primary Examiner. H. H. HUNTER, Assistant Examiner. 

